*The defeat of the Helvetii and Ariovistus: 58 B. C.* In 58 B. C., when Caesar entered upon his Gallic command, the Roman province in Transalpine Gaul (_Gallia __Narbonensis_) embraced the coast districts from the Alps to the borders of Spain and the land between the Alps and the Rhone as far north as Lake Geneva. The country which stretched from the Pyrenees to the Rhine, and from the Rhone to the ocean was called _Gallia comata_ or “long-haired Gaul,” and was occupied by a large number of peoples of varying importance. These were usually regarded as falling into three groups, (1) those of Aquitania, between the Pyrenees and the Loire, where there was a large Iberian element, (2) those called Celts, in a narrow sense of the word, stretching from the Loire to the Seine and the Marne, and (3) the Belgian Gauls, dwelling between these rivers and the Rhine. Among the latter were peoples of Germanic origin. Although conscious of a general unity of language, race and customs, the Gauls had not developed a national state, owing to the mutual jealousy of the individual peoples, and each tribe was perpetually divided into rival factions supporting different chiefs. Rome had sought to protect the province of Narbonensis by establishing friendly relations with some of these Gallic peoples and had long before (c. 121 B. C.) made an alliance with the Aedui. About 70 B. C. conditions in _Gallia comata_ had been disturbed by an invasion of Germanic Suevi, from across the Rhine, under their King Ariovistus. He united with the rivals of the Aedui, the Sequani, and after a number of years reduced the former to submission. In 59 B. C. he reached an agreement with Rome, became a “friend” of the Roman people, and, while abstaining from further aggression, remained firmly established in what is now Alsace. For some time the Roman province had been alarmed by the threat of a migration of the Helvetii, then settled in western Switzerland, and in March, 58 B. C., this people started in search of new abodes. Caesar reached Gaul in time to prevent their crossing the upper Rhone, and followed them as they turned westward into the lands of the Sequani and Aedui. Defeated in two battles, they were forced to return to their home and to become allies of Rome. The movement of the Helvetii had given Caesar the opportunity for intervention in _Gallia comata_, and a pretext for extending his influence there was found in the hostility of some of the Gauls to Ariovistus, and the knowledge that a band of Suevi was expected soon to cross the Rhine to reinforce the latter. To frustrate a German occupation of Gaul now became Caesar’s object. Ariovistus rejected the demands of Caesar, who thereupon attacked him, defeated him in the vicinity of Strassburg and drove him across the Rhine. Caesar was now the dominant power in Gaul, and many of the leading tribes entered into alliance with Rome. Of the Belgae, however, only the Remi came over to the side of Rome.